The synthesis of 1,1-difluoro-1-alkenes was achieved by the treatment dithioesters and thioketones with trimethylsilyl 2-fluorosulfonyl-2,2-difluoroacetate in presence a proton sponge catalyst, namely, 1,8-bis(dimethylamino)naphthalene. generated electrophilic difluorocarbene (:CF2) reacted thiocarbonyl functionalities to form 2,2-difluorothiirane intermediates, desulfurization which afforded p...

Thiocarbonyl compounds possess unusual photophysical properties: they fluoresce from S(2), phosphoresce from T(1) only at extremely low concentrations in solution at room temperature, have unit quantum yield of intersystem crossing from S(1) to T(1), undergo self-quenching at diffusion-controlled rates, and are quenched by ground-state oxygen leading to self-destruction. In this article, we are...

The reaction of a rhodanine derivative (= (Z)-5-benzylidene-3-phenyl-2-thioxo-1,3-thiazolidin4-one; 1) with (S)-2-methyl-oxirane (2) in the presence of SiO2 in dry CH2Cl2 for 10 days led to two diastereoisomeric spirocyclic 1,3-oxathiolanes 3 and 4 with the Me group at C(2) (Scheme 2). The analogous reaction of 1 with (R)-2-phenyloxirane (5) afforded also two diastereoisomeric spirocyclic 1,3ox...

Full details of the template-directed covalent cross-linking of duplex oligodeoxynucleotides are presented. 4-Thio-2'-deoxyuridine was incorporated synthetically into a 17mer oligodeoxynucleotide, and the thiocarbonyl group of the modified base was alkylated with a variety of alpha-bromoacetyl-derivatized diamines. Covalent cross-linking was initiated by annealing the electrophilic probe oligom...

A structure-activity relationship (SAR) study on 5-substituted oxazolidinones as an antibacterial agent is described. The oxazolidinones, of which 5-acetylaminomethyl moiety was converted into other functions, were prepared and evaluated for antibacterial activity. Elongation of the methylene chain (8) and conversion of the acetamido moiety into guanidino moiety (12) decreased the antibacterial...

Thermal decomposition of a mixture of the two stereoisomeric bis(2,5-dihydro-1,3,4-thiadiazoles) cisand trans-2, which was prepared by treatment of 2,2,4,4-tetramethylcyclobutane-1,3-dithione with excess of diazomethane in the presence of two equivalents of N-methylmaleimide, led to a mixture of three 1:2 cycloadducts of type 4. The structures of these thiocarbonyl methanide-adducts have been e...